Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-13T15:42:38.810Z Has data issue: false hasContentIssue false

The demography and ecology of the European shagPhalacrocorax aristotelis in Mor Braz, France

Published online by Cambridge University Press:  02 January 2013

Matthieu Fortin*
Affiliation:
Bretagne vivante, SEPNB, Réserve naturelle des marais de Séné, route de Brouël, 56860 Séné, France
Charles-André Bost
Affiliation:
CNRS, Centre d’études biologiques de Chizé, UPR 1934, 79360 Villiers en Bois, France
Philippe Maes
Affiliation:
Université de Bretagne Sud, Institut de Géoarchitecture, EA 2219, BP 573, 56017 Vannes, France
Christophe Barbraud
Affiliation:
CNRS, Centre d’études biologiques de Chizé, UPR 1934, 79360 Villiers en Bois, France
*
Get access

Abstract

An integrated research program was initiated to evaluate if the European shagPhalacrocorax aristotelis can be used as a robust indicator of themarine environment in Mor Braz, Brittany, France. This program focuses on aspects of theecology of the shag including its abundance, demography, diet and at-sea distributionmeasured at three breeding colonies. The annual population growth rate was estimated at1.01 for the period 1987–2009. The number of breeding pairs (mean: 565) was highlyvariable from year to year. Part of this interannual variation was explained by variationsin sea surface temperature and sea surface height in winter and spring: the number ofbreeding pairs was negatively related to sea surface temperature and sea surface height.First year, second year and adult survival probabilities were 0.44, 0.76 and 0.81,respectively. Juvenile survival rate varied between colonies, despite the short distancesseparating these islets. Average productivity was one young fledged per nest, but itvaried between years and islets. Density of individuals at sea varied between 1.40ind.km-2 during the breeding season and 3.08 ind.km-2 after thebreeding season had ended. Individuals foraged up to 7 km from the nest and performed onaverage 2.7 foraging trips per day. The average number of dives deeper than 5 m variedfrom 126 to 400 per day. Mean diving depth, dive duration and time spent at bottom were 13m, 28 s, and 19 s respectively. Regurgitated pellets were collected regularly. Four fishfamilies (Gadidae, Gobiidae, Atherinidae and Labridae) represented more than 65% of thepreys throughout the year, a percentage reaching more than 95% of the prey from May toOctober. The other fish in the diet were Cottidae, Ammodytidae, and Clupeidae. The diet ofthe European shag consisted of benthic fish throughout the year, and also included pelagicfish more frequently between June and October. The synchronous variations of productivitybetween colonies suggest that some common environmental factors affect this demographicparameter at the regional scale. Thus, the European shag has a good potential for being areliable ecological indicator of the state of this marine environment. Finally, improvedknowledge on the foraging ecology of shags will be useful in the process of designingMarine Protected Areas in the Mor Braz to help ensure sustainable management of marineresources and biodiversity conservation.

Type
Research Article
Copyright
© EDP Sciences, IFREMER, IRD 2013

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Aebischer, N.J., Wanless, S., 1992, Relationships between colony size and environmental conditions for shags Phalacrocorax aristotelis on the Isle of May, Scotland. Bird Study 39, 4352. CrossRefGoogle Scholar
Alvarez, D., 1998, The diet of shags Phalacrocorax aristotelis L. in the Cantabrian sea (North of Spain) during the breeding season. Seabird 20, 2230. Google Scholar
Barret, R.T., 1991, Shags (Phalacrocorax aristotelis L.) as potential samplers of juvenile saithe (Pollachius virens L.) stocks in Northern Norway. Sarsia 76, 153156. CrossRefGoogle Scholar
Barret, R.T., Røv, N., Loen, J., Montevecchi, W.A., 1990, Diets of shags Phalacrocorax aritotelis and cormorants P. carbo in Norway and possible interactions for gadoid stock recruitment. Mar. Ecol. Prog. Ser. 66, 205218. CrossRefGoogle Scholar
Bertram, D.F., Harfenist, A., Smith, B.D., 2005, Ocean climate and El Niño impacts on survival of Cassin’s auklets from upwelling and downwelling domains of British Columbia. Can. J. Fish. Aquat. Sci. 62, 28412853. CrossRefGoogle Scholar
Campana, S.E., 2004, Photographic atlas of fish otoliths of the northwest Atlantic Ocean. Can. Spec. Publ. Fish. Aquat. Sci. 133, 1284. Google Scholar
Camphuysen C.J., 2005, Understanding marine foodweb processes : an ecosystem approach to sustainable Sandeel fisheries in the North Sea. IMPRESS Report, Koninklijk Nederlands Instituut voor Onderzoek der Zee, Q5RS-2000-30864, Texel.
Caswell H., 2001, Matrix population models. Sinauer Associates, Sunderland, MA.
Choquet, R., Reboulet, A.M., Pradel, R., Gimenez, O., Lebreton, J.D., 2004, M-SURGE : new software specifically designed for multistate capture-recapture models. Anim. Biodiv. Conserv. 27, 207215. Google Scholar
Daunt, F., Afanasyev, V., Silk, J.R.D., Wanless, S., 2006, Extrinsic and intrinsic determinants of winter foraging and breeding phenology in a temperate seabird. Behav. Ecol. Soc. 59, 381388. CrossRefGoogle Scholar
Durant, J.M., Anker-Nilssen, T., Stenseth, N.C., 2003, Trophic interactions under climate fluctuations : the Atlantic puffin as an example. Proc. R. Soc. Lond. B Biol. 270, 14611466. CrossRefGoogle ScholarPubMed
Durant, J.M., Hjermann, D.Ø., Frederisken, M., Charrassin, J.B., Le Maho, Y., Sabarros, P.S., Crawford, R.J.M., Stenseth, N.Chr., 2009, Pros and cons of using seabirds as ecological indicators. Clim. Res. 39, 115119. CrossRefGoogle Scholar
Frederiksen, M., Harris, M.P., Daunt, F., Rothery, P., Wanless, S., 2004, Scale-dependent climate signals drive breeding phenology of three seabird species. Global Change Biol. 10, 12141221. CrossRefGoogle Scholar
Frederiksen, M., Mavor, R.A., Wanless, S., 2007, Seabirds as environmental indicators : the advantages of combining data sets. Mar. Ecol. Prog. Ser. 352, 205211. CrossRefGoogle Scholar
Frederiksen, M., Daunt, F., Harris, M.P., Wanless, S., 2008, The demographic impact of extreme events : stochastic weather drives survival and population dynamics in a long-lived species. J. Anim. Ecol. 77, 10201029. CrossRefGoogle Scholar
Furness, R.W., Camphuysen, K., 1997, Seabirds as monitors of the marine environment. ICES J. Mar. Sci. 54, 726737. CrossRefGoogle Scholar
Grémillet, D., Tuschy, I., Kierspel, M., 1998, Body temperature and insulation in diving great cormorants and European shags. Funct. Ecol. 12, 386394. CrossRefGoogle Scholar
Guyot I., 1988, Relationships between shag feeding areas and human fishing activities in Corsica (Mediterranean Sea). In : Tasker M.L. (Ed.) Seabird food and feeding ecology. Proc. 3rd Intl. Conference of the Seabird Group, Sandy, pp. 22–23.
Harding A.M., Piatt J.F., Sydeman W.J., 2005, Bibliography of literature on seabirds as indicators of the marine environment. USGS Alaska Science Centre, Anchorage, available at http://alaska.usgs.gov/science/biology/seabirds_foragefish/sai/
Harkönen T., 1986, Guide of the bony fishes of the northeast Atlantic. Danbiu ApS. Biological consultants.
Harris, M.P., Riddiford, N.J., 1989, The food of some young seabirds on Fair Isle in 1986-88. Scottish Birds 15, 119125. Google Scholar
Harris, M.P., Wanless, S., 1991, The importance of the lesser sandeel Ammodytes marinus in the diet of shag Phalacrocorax aristotelis. Ornis Scand. 22, 375382. CrossRefGoogle Scholar
Harris, M.P., Buckland, S.T., Russell, S.M., Wanless, S., 1994, Year- and age-related variation in the survival of adult European shags over a 24-year period. Condor 96, 600605. CrossRefGoogle Scholar
Harris, M.P., Anker-Nilssen, T., McCleery, R.H., Erikstad, K.E., Shaw, D.N., Grosbois, V., 2005, Effect of wintering area and climate on the survival of adult Atlantic puffins Fratercula arctica in the eastern Atlantic. Mar. Ecol. Prog. Ser. 297, 283296. CrossRefGoogle Scholar
Johnstone, I.G., Harris, M.P., Wanless, S., Graves, J.A., 1990, The usefulness of pellets for assessing the diet of adult shags Phalacrocorax aristotelis. Bird Study 37, 511. CrossRefGoogle Scholar
Kitaysky, A.S., Golubova, E.G., 2000, Climate change causes contrasting trends in reproductive performance of planktivorous and piscivorous alcids. J. Anim. Ecol. 69, 248262. CrossRefGoogle Scholar
Lombarte, A., Chic, Ò., Parisi-Baradad, V., Olivella, R., Piera, J., García-Ladona, E., 2006, A web-based environment from shape analysis of fish otoliths. The AFORO database. Scient. Mar. 70, 147152. Google Scholar
Lumsden, W.H.R., Haddow, A.J., 1946, The food of the shag (Phalacrocorax aristotelis) in the Clyde sea area. J. Anim. Ecol. 15, 3542. CrossRefGoogle Scholar
Mills, D., 1969, The food of the shag in Loch Ewe, Ross-Shire. Scottish Birds 5, 264268. Google Scholar
Pannekoek J., van Strien A.J., Roby D., 2004, TRIM (Trends and indicators for monitoring data). Statistics Netherlands, Vooburg.
Pasquet E., 1987, Relationships between Brittany shags and seawaters resources. Muséum National d’Histoire Naturelle, Centre de recherches sur la biologie des populations d’oiseaux, Paris.
Pearson, T.H., 1968, The feeding ecology of sea-bird species breeding on the Farne Islands, Northumberland. J. Anim.. Ecol. 37, 53102. CrossRefGoogle Scholar
Piatt, J.F., Harding, A.M.A., Shultz, M., Speckman, S.G., van Pelt, T.I., Drew, G.S., Kettle, A.B., 2007, Seabirds as indicators of marine food supplies : Cairns revisited. Mar. Ecol. Prog. Ser. 352, 221235. CrossRefGoogle Scholar
Ridgway, M.S., 2010, Line transect distance sampling in aerial surveys for double-crested cormorants in coastal regions of Lake Huron. J. Great Lakes Res. 36, 403410. CrossRefGoogle Scholar
Steven, J., 1933, The food consumed by shags and cormorants around shores of Cornwall (England). J. Mar. Biol. Assoc. UK 19, 277292. CrossRefGoogle Scholar
Thomas, L., Buckland, S.T., Rexstad, E.A., Laake, J.L., Strindberg, S., Hedley, S.L., Bishop, J.R.B., Marques, T.A., Burnham, K.P., 2010, Distance software : design and analysis of distance sampling surveys for estimating population size. J. Appl. Ecol. 47, 514. CrossRefGoogle Scholar
Tramer, E.J., 1969, Bird species diversity : components of Shannon’s formula. Ecology 50, 927929. CrossRefGoogle Scholar
Velando, A., Freire, J., 1999, Intercolony and seasonal differences in the breeding diet of European shags on the Galician coast (NW Spain). Mar. Ecol. Prog. Ser. 188, 225236. CrossRefGoogle Scholar
Velando, A., Freire, J., 2002, Population modelling of European shags (Phalacrocorax aristotelis) at their southern limit : conservation implications. Biol. Conserv. 107, 5969. CrossRefGoogle Scholar
Wanless, S., Harris, M.P., Morris, J.A., 1991, Foraging range and feeding locations of shags Phalacrocorax aristotelis during chick rearing. Ibis 133, 3036. CrossRefGoogle Scholar
Wanless, S., Harris, M.P., Russell, A., 1993, Factors influencing food-lead sizes brought in by shags Phalacrocorax aristotelis during chick rearing. Ibis 135, 1924. CrossRefGoogle Scholar
Wanless, S., Harris, M.P., Burger, A.E., Buckland, S.T., 1997, Use of time-at-depth recorders for estimating depth and diving performance of European shags. J. Field Ornithol. 68, 547561. Google Scholar